Copper smelting and separating.



No. 788,589. PATENTBD MAY 2', 1905. G. MITCHELL.

COPPER SMELTING AND SBPARATING.

APPLIOA'TION FILED FEB. 29.1904.

NiTEn STATES Patented May 2, 1905.

GEORGE MITCHELL, OF LOS ANGELES, CALIFORNIA.

COPPER SlVlELTlNG AND SEPARATING.

SPECIFICATION forming part of Letters Patent No. 788,589, dated May 2,1905.

Application filed February 29, 1904,. Serial No. 195,928.

To all whom it may concern:

Be itknown that I, Grzonen MITCHELL, of Los Angeles, in'the county ofLos Angeles and State of California, have invented certain new anduseful Improvements in Copper Smelting and Separating; and I do herebydeclare the following to be a full, clear, and exact description oftheinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

My invention relates to improvements in the the art of copper smeltingand separating, the object of the invention being to provide a processof reducing and separating copper from its ore, which shall result ineconomy of fuel.

With this object in view the invention consists in certain novel stepsin the reduction and separation of copper, as hereinafter set forth, andpointed out in the claims.

In the accompanying drawings, Figure 1 represents a smelting-furnace,and Fig. 2 a converter, with the use of which my improved process may becarried into effect.

1 represents a furnace of the reverberatory variety having afurnace-chamber 1, a smelting-chamber 2, having a hearth 3 and a well4:, and provided in its top with a charginghole'5.

A converter is represented at 6 and mount cd to rock in a frame 7.

The particular constructions of the furnace and converter shown are notessential to the carrying out of my improved process, as vasubject thecrushed ore, without the admixture therewith of any carbonaceous orother fuel not already contained in the ore, to a sufficientdegree ofheat in a reducing atmosphere within the smelting-furnace to effectfusing,

admitting only suiiicient air to support combustion and avoiding thepresence of suiiicient oxygen to cause a chemical union of the metallicportion with silica. ner the crushed ore will be so smelted as to fusethe metal without formingsilicates-that is to say, the metallic portionof the ore will be fused, leaving the silica (when silicious ores arebeing smelted) behind and unattached by-the metallic portion, the amountof oxygen in the furnace during the smelting operation being kept at aminimum by reason of the fact that the ore has not been oxidized byroasting and by reason of the introduction of a limited amount of airinto the furnace. Thus the expensive operation of roasting is avoided.Furthermore, I am enabled to save the enormous amount of fuel consumedin present smelting processes of separating metals from silica byforming silicates of them, as occurs in the smelting of roasted ores. Itmay sometimes be found desirable, in order to further economize fuel. tochange the atmosphere of the furnace from time to time by the admissionof a small amount of air, which would cause a slight oxidizing action,and heat would be thereby obtained by oxidation of the sulfur and themetals and the breaking up of some of the chemical constituents of someores. The fused matte, minus'thesilica or silicious matter-,(whensilicious ores are beingsmelted,) will be driven or drawn off from timeto time or in a continuous stream, according to the amount of oresmelted. The matte thus drawn off in a molten condition will be chargedinto a Bessemer converter, which can be lined with a basic or anacidlining, as may be best suited as conditions would demand in certainlocali ties.

The hot silica that is left behind in the smelting-furnace and fromwhich the metal has been separated, as above explained, will be removedfrom time to time and fed into the converter to obtain the benelit oflengthening the life of thelining of the converter and also to assist ingiving silica more readily and rapidly to the oxids that are beingformed in the converter, which results are most ellicaciousl y andthoroughly accomplished because of the hotand chemically-unchangedcondition of the In this mansilica as it comes from thesmelting-furnace, the oxids being changed into silicates in theconverter rather than in the smelting-furnace.

It is apparent that by fusing only the metals in the ores in thesmelting-furnace, avoiding the formation of silicates, there will resulta very great saving of the fuel which has heretofore been necessary toseparate metals from the silica when during the smelting operation achemical union of the metals with the silica has been permitted. By myprocess a further saving of fuel is accomplished and the lining of theconverter is most effectually preserved by transferring the hot silicadirc 3tlyfrom the smelting-furnace to the converter.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is'- 1. The process of separating siliciousore, which consists in subjecting the raw ore to a reducing atmospherein a smelting-furnace, fusing it therein, avoiding the chemical union ofthe metal with silica in the smelting-furnace. and withdrawing themolten matte.

2. The process of separating silicious copper ore, which consists infusing the metal in a smelting-furnace; avoiding the union of the metalwith silica, withdrawing the fused matte in molten condition andseparately withdrawing the silica.

3. The process of separating silicious ore, which consists in fusing themetal and separating it from the silica; avoiding the union of the metalwith the silica, withdrawing the molten matte and silica separately, andsubsequently utilizing the hot silica in a converter.

4. The process of separating silicious ore, which consists in subjectingthe ore to a reducing atmosphere in a smelting-furnace; fusing ittherein, avoiding a chemical union of the metal and silica, and thenwithdrawing the molten matte, leaving the silica behind.

5. The process of separating silicious ore, which consists in crushingraw ore and discharging it into a smelting-furnace; subjecting the oreto a reducing atmosphere within the smelting-furnace; fusing it thereinavoiding the union of metal and silica; Withdrawing the molten matte;discharging it into a converter then withdrawing the silica anddischarging it into the converter.

6. The process of separating copper ore, which consists in subjectingraw ore to a reducing atmosphere in a smelting-furnace, fusing ittherein, withdrawing the molten matte from the smelting-furnace, anddischarging said metal while hot into a converter.

7. The process of separating silicious copper ore, which consists insubjecting the raw ore to a reducing atmosphere in a smeltingfurnace,avoiding the chemical union of the metal with silica in thesmeltingfurnace, withdrawing the molten matte from the smelting-furnaceand discharging it while hot into a converter.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

GEORGE MITCHELL. Witnesses:

HARRY Gr. HEGHT, N. J. MAcPHERoN.

